Progression to ESRD in Biopsy-Confirmed Amyloidosis in a Hispanic Population: A Retrospective Study

Background: Amyloidosis is a disease of misfolded proteins leading to multi-organ dysfunction through tissue deposition. There are 3 main variants of amyloidosis (AL - Light chain, AA - Amyloid A, and ATTR - Transthyretin). AL results from secretion of light chains (typically lambda light chains) often associated with abnormal plasma cell clones such as multiple myeloma. AA develops from sustained elevation of serum amyloid, an acute-phase reactant. The disease may manifest with variable organ systems affected, our study focused on renal involvement including nephrotic range proteinuria that progresses to ESRD. Data on amyloidosis in U.S. Hispanic populations is limited but suggest significant disease burden. Methods: We conducted a retrospective chart review of Hispanic patients with biopsy-confirmed amyloidosis with renal involvement between the dates of April 2014 and May 2025 at a single Nephrology clinic. Variables included urine protein-to-creatinine ratio (UPCR), hepatitis C antibody positivity, and time from diagnosis to dialysis treatment. Results: A total of 17 out of 254 patients were identified with biopsy-proven amyloidosis from April 2014- May 2025. The mean age was 46 years, and 50% were male. AA amyloidosis accounted for 83% of cases with AL for 17%. Hypertension and diabetes were present in 55% and 22%, respectively. Median UPCR was 12.29 g/g, with an average eGFR of 13.46 mL/min and mean serum creatinine of 5.67 mg/dL. Progression to ESRD occurred in 72% of patients with median diagnosis to first dialysis of 1.5 months. In the AA group, 93% were positive for hepatitis C. Conclusion: AA amyloidosis was the most prominent type in this cohort and strongly associated with hepatitis C. Proteinuria and progression to ESRD requiring dialysis were very common in our cohort. Hepatitis C is known to upregulate production of SAA-inducing cytokines and due to chronic inflammation leads to sustained elevation of SAA that can lead to development of AA amyloidosis. Compared to prior data from non-US hispanic populations, our cohort presented with higher rates of progression to ESRD requiring dialysis and a stronger link to hepatitis C in AA amyloidosis cases. These findings underscore the link between hepatitis C and AA amyloidosis in this vulnerable population, particularly in the US.